<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <div>
        <input type="text" v-model="n1">
        <input type="text" v-model="n2">
        <input type="button" value="加" @click="f(1)">
        <input type="button" value="减" @click="f(2)">
        <input type="button" value="乘" @click="f(3)">
        <input type="button" value="除" @click="f(4)">
        <div>
            结果：{{result}}
        </div>
    </div>
<script src="https://cdn.staticfile.org/vue/2.2.2/vue.min.js"></script>
    <script>
        let v=new Vue({
            el:"body>div",
            data:{
                result:"",
                n1:"",
                n2:"",
            },
            methods:{
                f(x) {
                    switch (x) {
                        case 1:
                            v.result=v.n1*1+v.n2*1;
                            break
                        case 2:
                            v.result=v.n1-v.n2;
                            break
                        case 3:
                            v.result=v.n1*v.n2;
                            break
                        case 4:
                            v.result=v.n1/v.n2;
                            break
                    }
                }
            }
        })
    </script>
</body>
</html>